Electric lamp socket



Feb. 23 193?; A, WOLF 2,@71,445

ELECTRIC LAMP SOCKET Filed Sept. 26, 1934 BYM 2 a ATTORNEY Patented Feb. 23, 1937 UNITED STATES PATENT oFFIcE Electric Corporation,

New York, N. Y., a corporation of New York Application September 26, 1934, Serial No. 745,569

Claims.

This invention relates to electric lamp sockets.

An object of this invention is to provide a socket of the character described, which shall be extremely cheap to construct, easy to assemble and wherein the parts will be firmly retained in assembled relation without looseness developing during use.

A further object of this invention is to provide a compact socket of the character described having highly improved means for retaining the screw shell within the socket housing.

Another object of this invention is to provide a strong and durable lamp socket for outdoor illumination, having improved means for waterproofing the socket and relieving strain on the terminal connections, and which shall be practical and eflicient to a high degree in use.

Other objects of this invention will in part be obvious and in part hereinafter pointed out.

The invention accordingly consists in the features of construction, combinations of elements and arrangement of parts which will be exemplified in the construction hereinafter described and of which the scope of application will be indicated in the following claims.

In the accompanying drawing, in which is shown one of the various possible embodiments of this invention,

Fig. 1 is an axial, cross-sectional view of a lamp socket embodying the invention, 7

Fig. 2 is a top plan view of my improved lamp socket,

Fig. 3 is a cross-sectional view taken on line 3--3 of Fig. 1,

Fig. 4 is a cross sectional view taken on line 4--4 of Fig. 1,

Fig. 5 is a top plan view of the socket housing without the cap,

Fig. 6 is a bottom plan view of the under side of the cap; and

Fig. 7 is a side elevational view of my improved socket with a lamp attached thereto.

Referring now in detail to the drawing, In designates a lamp socket embodying the inveni tion, having attached thereto a lamp II and being connected in parallel across a pair of insulated lead wires l3 and M. The socket 10 comprises a housing l5 made of insulating material and a cap l6 likewise made of insulating material and attached thereto in the manner hereinafter explained. The housing l5 comprises a tubular portion l8 having an outwardly flaring mouth l9 and an end wall at the upper end thereof. For the purpose hereinafter appearing, the tubular portion I8 is formed adjacent the flaring mouth thereof with an annular, shallow groove 22.

On the inner surface thereof the end wall 20 is formed with a central, downwardly extending projection 24, and with a pair of parallel, symmetrically disposed walls 26, forming therebetween a groove 21'. The walls 26 do not extend entirely across the end wall 20, but are disposed on one side only of the projection 24. Said end wall 20 is formed with a pair of through openings 28 and 29 disposed on a diametric line parallel to and equally spaced from the walls 26.

On the upper surface thereof, the end wall 20 is provided with a pair of parallel, substantially semi-cylindrical, symmetrically disposed grooves 30 and 3! communicating with the openings 28 and 29 respectively. At the upper ends thereof, the openings 28 and 29 have enlarged, circular portions 28a and 29a forming flat, circular surfaces. The grooves 30 and 3| are formed with a plurality of thin, narrow ridges 30a. and 3la, for the purpose hereinafter appearing. The end wall 20 is further formed in the upper surface thereof with an upwardly extending axial projection 33 and with an axial opening 34 extending through said projection and being sufliciently deep to enter the projection 24, but terminating short of the lower surface thereof.

Received within the housing H5 is a lamp base receiving screw shell 40. Said screw shell has an outer rim edge 4| somewhat outwardly flaring and being formed with a plurality of spaced slits or notches 42. Upon forcing the shell into the housing, the rim 4|, which is rendered somewhat resilient by the slits 42, snaps into the annular groove 22 to prevent the shell from falling out of the housing.

The shell is formed with a rear or upper wall 44 having an opening 45. The shell is also attached to the housing by an eyelet 45 which extends through the opening 45 and the opening 29 in end wall 20, the upper end of the eyelet being received within the enlarged portion 29a of said opening 29. The upper wall 44 of the shell is cut away as at 41 to receive the projection 24 and the walls 26. The threaded portion of the shell is also cut away as at 48 on the side thereof adjacent the cut away portion 41. Received between the walls 26 is one end portion 50 of a strip of metal 5! attached to the end wall 20 by an eyelet 52 extending through opening 28 in said end wall and through an opening in said end portion 50. The upper end of the eyelet 52 is received within the enlarged portion 28a of the opening 28. The strip 51 also comprises a foldedback spring portion 55 disposed below the projection 24 serving as a central contact for the socket.

The insulated wires I3 and I4 are received within the grooves 30 and 3| and bared portions I311. and Ma of said wires may be fixed to the eyelets 52 and 45 by soldering or by the folded-over portions of the eyelets pressing said bared portions within the enlarged openings 28a and 29a, or in any other suitable manner.

The cap I6 registers or fits over the end wall 20. On the under side thereof, the cap is formed with a pair of parallel, symmetrically disposed, substantially semi-cylindrical grooves 60 and 6| registering with the grooves 30 and 3I to form cylindrical through openings for the insulated wires I3 and I4. The grooves 60 and 6| are formed with narrow, thin ridges 60a and Sla similar to the ridges 30a and 3Ia of the grooves 30 and 3|. Said cap is further formed with an axial through opening 63 countersunk at the upper end thereof as at 64. At the lower end thereof the opening 63 is likewise countersunk as at 65 to receive the projection 33 on the end wall 20. The grooves 60 and BI may be formed with circular depressions 61 and 68 aligned with the large portions 28a and 29a of the openings 28 and 29. The cap I6 may be attached to the housing I5 by means of a drive screw I having a head II received within the countersunk portion 64, and a shank I extending through the opening 63 and into the opening 34. The shank of the screw preferably loosely fits Within the opening 63 but is forced into the opening 34 cutting threaded grooves into the wall of said opening upon being driven thereinto.

It will be noted that the opening 34 extends into the projection 24. Said projection therefore permits a sufficiently long opening for receiving the shank of the drive screw. Furthermore, the spring end 55 abuts against the under surface of said projection upon screwing the lamp I I to the screw shell 40. The ridges a, 3Ia, and 50a, BIa press against the insulation of the wires I3, I4 upon attaching the cap to the housing, thus acting as a strain relief means to prevent breaking of the connection between the wires and the eyelets 52, 46. Said ridges also prevent seepage of water or moisture into the housing through the passages which receive the insulated wires, thus rendering the socket substantially waterproof. As shown in Fig. 3, the ridges pressing against the insulated wires form grooves or depressions 72.

It will thus be seen that there is provided a device in which the several objects of this invention are achieved and which is well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the above invention and as various changes might be made in the embodiment set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawing is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1-. An electric lamp socket comprising a tubular insulating housing having an end wall, said end wall having a projection on the inner surface thereof and being formed with a pair of through openings, a screw shell within said housing attached to said end wall by a member extending through one of said through openings, a strip of metal fixed to said end wall by a member extending through the other of said through openings and having a resilient free end portion forming a central contact and disposed below said projection, said end wall being formed with an opening in the top thereof extending into said projection, and a cap fitted over said end wall and being attached thereto by a drive screw extending through said cap and into said last mentioned opening, the end of said drive screw extending into said projection.

2. An electric lamp socket comprising an insulated tubular housing having an end wall, a screw shell within said housing having an outwardly extending annular rim, a central contact attached to the inner surface of said end wall, the inner surface of said housing being formed with an annular groove receiving said rim, said end wall having an axial projection on the inner surface thereof and being formed with a pair of parallel grooves on the outer surface thereof, insulated wires within said grooves attached to the central contact and screw shell, and a cap received on the end wall and being formed with a through opening, said end wall being formed with an axial opening on the outer surface thereof extending into said projection, and a drive screw extending through the opening in said cap and into said opening of said end wall for attaching the cap to the housing.

3. An electric lamp socket comprising an insulated tubular housing having an end wall, a screw shell within said housing having an outwardly extending annular rim, a central contact attached to the inner surface of said end wall, the inner surface of said housing being formed with an annular groove receiving said rim, said end wall having an axial projection on the inner surface thereof and being formed with a pair of parallel grooves on the outer surface thereof, insulated wires within said grooves attached to the central contact and screw shell, a cap received on the end wall and being formed with a through opening, said end wall being formed with an axial opening on the outer surface thereof extending into said projection, and a drive screw extending through the opening in said cap and into said opening of said end wall for attaching the cap to the housing, said pair of grooves being formed with ribs engaging said insulated wires.

4. An electric lamp socket comprising an insulated tubular housing having an end wall, a screw shell within said housing having an outwardly extending annular rim, the inner surface of said housing being formed with an annular groove receiving said rim, said end wall having an axial projection on the inner surface thereof and being formed with a pair of parallel grooves on the outer surface thereof, a strip of metal attached to the inner side of the end wall and having a free end portion terminating below said projection, insulated wires within said grooves attached to said strip and screw shell, 2. cap received on the end wall and being formed with a through opening, said end wall being formed with an axial opening on the outer surface thereof extending into said projection, a drive screw extending through the opening in said cap and into said opening of said end wall for attaching the cap to the housing, said pair of grooves being formed with ribs engaging said insulated wires.

5. An electric lamp socket comprising an insulated tubular housing having an end wall, a screw shell within said housing having an outwardly extending annular rim, a central contact attached to the inner surface of said end wall, the inner surface of said housing being formed with an annular groove receiving said rim, said end wall having an axial projection on the inner surface thereof and being formed with a pair of parallel grooves on the outer surface thereof, insulated wires within said grooves attached to the central contact and screw shell, and a cap received on the end wall and being formed with a 10 through opening, said end wall being formed with an axial opening on the outer surface thereof extending into said projection, and a drive screw extending through the opening in said cap and into said opening of said end Wall for attaching the cap to the housing, the annular rim of said screw shell being slotted to permit the rim to snap into said annular groove upon inserting the shell within the housing. 

